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Perfluorinated Trialkoxysilanol with Dramatically Increased Bronsted Acidity.

ABSTRACT: The Brønsted acidity of the perfluorinated trialkoxysilanol {(F₃ C)₃ CO}₃ SiOH is more than 13 orders of magnitude higher than that of orthosilicic acid, Si(OH)₄ , and even more for most previously known silanols. It is easily deprotonated by simple amines and pyridines to give the conjugate silanolates [OSi{OC(CF₃ )₃ }₃ ]^- , which possess extremely short Si-O bonds, comparable to those of silanones.

SUBMITTER: Feige F

PROVIDER: S-EPMC9292728 | biostudies-literature | 2021 Nov

REPOSITORIES: biostudies-literature

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Perfluorinated Trialkoxysilanol with Dramatically Increased Brønsted Acidity.

Feige Felix F Malaspina Lorraine A LA Rychagova Elena E Ketkov Sergey S Grabowsky Simon S Hupf Emanuel E Beckmann Jens J

Chemistry (Weinheim an der Bergstrasse, Germany) 20211014 64

The Brønsted acidity of the perfluorinated trialkoxysilanol {(F3 C)3 CO}3 SiOH is more than 13 orders of magnitude higher than that of orthosilicic acid, Si(OH)4 , and even more for most previously known silanols. It is easily deprotonated by simple amines and pyridines to give the conjugate silanolates [OSi{OC(CF3 )3 }3 ]- , which possess extremely short Si-O bonds, comparable to those of silanones. ...[more]

PMID: 34550614

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